*& 



QB 67 
.W6 
1875 
Copy 1 



\vis 



he number of the Stars ; He calleth them all by their names. | 

Op 



l'SALMS. Cxlvii, i. 




-t,> 



A KEY TO THE 

MOVABLE PLANXSPHE-™, 

WHICH SHOWS THE POSITION OF 

THE HEAVENS AT EVERY MINUTE, 






PY 



HEN BY WHITALL, 

512 -AJFL03E3C SJTDFL3E33S3T, FIBEXT » AT->:ESXj3F»:BCX.A.. 



SJSNJ) $6, AJXD BY RETUKN MA.IL GET jL FULL SET. 

J£gg~ Used with the As-tronomy of Dr. Jayne's Almanac 



itii. ace. to Act o' Congress, in the year 1875. by Hsmky Whitaia, in the office of the Librarian ot Congress at Washington, D. • 




W$ : 



LUflTATELLUS. 

Sent by Express, $40. CO. D. 

The Limatellus lias 45 illustrations with 25 
pages of explanations, showing clearly the 
direction of the motions of the Sun. Earth 
and Moon in their natural order, with the 
Geography of the Earth always in its proper 
relation to them. The plane of the Ecliptic 
crossing the Equator. When the Axis is so 
placed as to point North arid South it always 
keeps parallel. The Earth tarns from West 
to East for day and night, naturally. Days 
equal, long, or short, and why. Six Months day 
at one pole, night at the other, and when. 
Change of seasons and causes. Zones and 
width. Winter when the Earth is nearest, 
and "Summer when farthest from the Sun. 
Sun rising North in Summer, South in Winter. 
Why the Sun rises earlier East of us. Ap- 
parent motion of the Sun, Moon and Stars 
from East to West while the Earth is realy 
moving from West to East. Suns declination, 
and relative position, any time in one sign, 
while the Earth is in the opposite sign. Ellip- 
ticity of Earth's orbit, Siderial and Solar day. 
Tides, spring, neap, solar and lunar. Winds, 
periodic, trade, Monsoons, &c. The Moon 
keeps the same side to the Earth, length of 
days and nights. 

Conjunction, quadrature, opposition and 
phases, Ellipticity of Moons orbit, apogee 
and perigee, and its plane to the Ecliptic. 
Nodes changes, Synodical and siderial revolu- 
tions. Eclipses, Snn, Moon, and cause. Full 
Moon North in Winter, South in Summer. 
First quarter loio, Third quarter high, and 
when. First quarter high, Third quarter low, and 
when. Moon's librations, Zenith, Nadir, Hori- 
i zon. Verticle circles, prime vertical and co- 
lures. Circles of perpetual apparation and 
occultation. Sun's zenith distance, altitude 
and declination for any latitude or time. 
Spheres, right, oblique or parallel. Azimuth 
and amplitude on or above the Horizon. All 
so naturally and truthfully shown as to please 
and astonish the learned or unlearned when 
they will take the pleasure to look into their 
real merits, will find "the half has not yet 
been told." 




HELIOTELLUS. 



Sent by Express, $6 5. or the two for $ 1 00, C. O. D 
The Heliotellus shows all the Lunatellu 
does and Mercury and Venus. Having 62 i 
lustrations, 35 pages explanation accompan 
each one, so as very naturally to show Me 
cury's yearly and daily revolutions. Axis pe 
pendicular and parallel, days and nights eau«i,- 
no change of seasons. Conjunctions ■iuferiov or 
superior, stationary points, when visible, 
phases, &c. Also of Venus' yearly and daily 
revolutions. Inclination of axis and keep 
IDarallel, and moves in its natural orbit. Sur 
declination. Eight seasons at Equator, ic 
at her Poles. Morning and Evening S 
Synodic period, Phases, Transits, Occultat:' , 
Accuracy in giving just conceptions of the 
fundamental principles of Science, Illusirat- 
ing the great mechanism of the Solar System, 
Mutual relations of Geography and Astronomy. 
The natural causes and phenomena so easily 
illustrated, which cannot be learned from 
Maps or Charts, which oil other Apparatus fail 
to do so well. With them knowledge is so 
easily imparted or acquired, and their natural 
movements make upon the mind such lasting 
impressions ; they are so beautiful, as to be an 
ornament of practical value in a library, reci- 
tation room, or scientific gentleman's parlor, 
and save a vaste amount of time in making a 
practical illustration of the daily changes, we 
see above and around us, are a few of their 
many uses. 

No one can make the Lunatellus and Helio- 
tellus without tools, the better the tools the 
better the work. The difference in teachers, 
is the tools and their knowledge and willing- 
ness to use them for the benefit of their pupils. 
The first made cost between $200. and $300. 
each to make, but by an outlay of $25,000. for 
machinery and tools they are now so perfect, 
and can be sold so low and are so invaluable, 
they should be in every school and family of 
intelligence and refinement. AGENTS want- 
ed everywhere, who can buy a dozen at one- 
third off, or a gross at a-half off, for cash, 
each one well packed into a box, with full ex- 
planations, so as to be safely expressed to any 
place. Have but a few left on hand, not 



enough to sell to, one in a hundred that 
should and would have them if rightly known 
and understood, for real value and usefulness.. 
When all are sold out, cannot be duplicated, 
; for less than $250 each, as the expensive tools, 
that turned them out so cheap, nave all been 
destroyed, so said the one that made them, 
that "no more should ever be made," so buy 
quick, "now is the accepted time." 

The intelligent Teacher who will give a few 
hours si-ady to the illustrations with the Lu- 
natellus and Heliotellus will soon be well pre- 
pared to give Celestial Object Lessons of Hav- 
enly beauty ; they move so truly to nature, it 
will never" be necessary to shock the pupils 
acute sense of truthfulness by denying what is 
once told, (as with the Orrery, we do not 
mean, the Earth moves in the horizon, and 
revolves ' from North to South, or South to 



North, and points near the Zenith for the 
North Pole, but we do mean, and) by these 
show, that the Earth moves in the Ecliptic, 
when set so the Axis points North and South, 
revolves from West to East. Never getting 
as far out of the true line, as the Orrery never 
comes into the true line. These as true to 
nature, as the others to the wrong, coming 
much nearer to the real, than any other in- 
struments made, a careful examination will 
make their intrensic value apparent to all. 
A very great improvement has been discovered 
that doubles their lasting value which will be 
added to all sold by Henry Whitall, Prof, of 
Astronomy, Park Institute, 859 Sixth Ave., 
New York. Permanent address, 512 Arch St., 
Philadelphia, Pa., all letters remailed to me as 
I move. 



PREFACE. 



We have six different Planispheres, which 
took the first Medal and Diploma at the grand 
Fair of the Amerioan Institute, 1869. No. 1 
was made in 1856, with the Constellations very 
beautifully painted like the Celestial Globe, 
and is sold for $3. No. 2 was made in 1862, 
to look like the sky, black ground, stars white : 
sold for $3. Both are now very much im- 
proved, and make a complete set: sent by mail 
on the receipt of §6. No. 3 includes Nos. 1 
and 2 in oue; ground black, stars, Constella- 
tions, and names white. Got up like a book, 
j Planisphere on one large cover, the Rules on the 
other cover: sold or sent by mail, $5. No. 4, 
stars and names black, Constellations colored 
to their boundaries ; got up for the new Amer- 
ican Constellation, formed out of many others, 
in honor of U. S. Grant, President, by J. T. 
Sweet, of Telescope, Fifth Avenue and Twenty- 
Third Street, N. Y. : sold or sent by mail on re- 
ceipt, of $3. No. 5 is a small one, being an 
exact copy of a large one, prepared for the 
purpose of being put on the inside of the cover 
of all Astronomies ; for size see title page : sold 
or sent by mail on receipt of 75 cents. No. 6 
is very nicely photographed on glass, in a 
mahogany frame, with brass cog-wheels, set at 
any minute as explained, for a stereoptican or 
magic lantern: Stars and Constellations like 
the Celestial Globe, sold for $6. No. 7 same 
as No 6, only more natural showing the stars 
I like the sky: sold ibr $6. The two make a set: 
j sent by Express for $12, C.O.D., and may be 
; put on a screen twenty or fifty feet in size, and 
j be black, so that all the light will shine through 
the darkness, and show the stars as lights very 
naturally, so much like the sky that the large 
stars may be learned in an hour or so. 

Most every Teacher knows more or less of 
Astronomy, and often get to talking about some 
Constellation or Planet, or wonder what is that 
star by the moon, all such will find the 
Planisphere to the sky, what a Directory is to 
the City, for any minute in the day found on 
the movable horizon, can be brought to any 
day found on the Planisphere. Then in the ho- 
• rizon will be seen the star just so far above the 
horizon, as then seen with the name along side 
it. Should it be a planet, we wc.it it will not 
be found on the Planisphere, but oy rule, 9 on 
page 7, and the Almanac, we can locate it. 



Many attend a lecture on Astronomy, and 
probably carried away in rapture and going 
out look on the sky, but cannot tell which is 
the one spoken of, to such I will say take the 
Planisphere, for it is to the sky what a map is 
to the study of Geography. 

I received two lessons that made the most 
lasting impressions upon my mind. First by 
my dear aunt Jane, who showed me many of 
the stars and their interesting beauties, when 
I asked, what bright star is that? not being- 
answered, raised in me a desire if I ever got 
big, I would know them all. When I graduated 
I could calculate an Almanac, but not name a 
star when I saw it. While teaching at Cole- 
town, N. J., the Hon. John W. Hazleton, after 
his brilliant speach at our debate, gave me the 
second lesson, and by far the greatest of my 
life. Calling each star by name with a famili- 
arity that struck me with pleasure and delight, 
I asked him where he got his knowledge from, 
he told me from Burritt's Geography of the 
Heavens; as soon as it was in my power, 
owned that treasure, being a teacher and try- 
ing to overcome the difficulties met with 
brought out Maps of the whole Heavens, as 
we see it. 21 years improvement brought me 
to my moveable Planisphere, with them I have 
solved many new, hard and difficult problems, 
I never knew before, one the Eaquation of time 
Burritt, page 201. "It appears that from Ariese 
to Cancer, the Sun in the ecliptic comes to the 
meridian before the equinoctial Sun." With 
the Figure by it I would study, until my head 
would ache, at times for 15 years, and neither 
understood it nor met with any one to tell me. 
I solved the trouble by the Planisphere thus: 
Bring the Meridian to 30° R. A. on the equi- 
noctial, clock time, I see 30° on the ecliptic 
Sun time appears slow going from the vernal 
equinox to the summer solstice as the Sun 
moves through April, May and June, see his 
place where the day of the month is, it looks 
as though it had not yet arrived at the Meridian 
is the point I could not understand until I saw 
the whole on the face of the Planisphere, 
showing what I was wanting to see, the east 
whese the sun rises, then coming to the Me- 
ridian, showing the Sun past the Meridian to- 
wards the west, see rule 19, page 8. 



THE TWELVE SIGNS AND THE CONSTELLATIONS. 



TWELVE SIGNS OF THE ZODIAC. 

ftCr The names of the Constellations and Stars are 
accented on each Planisphere. 

A'RI-ES (the Ram) Avas 2155? years passing 
over the vernal equinox. While there, it was 
[ correct to say first point A'ri-es ; as it has gone 
away, never to return, why not say first point 
Pis'ces? but Astrology demands, Astronomy 
consents, one sign in the rear. 

1. T 3g PIS'CES (the Fishes), at 
the vernal equinox, where the ecliptic and equa- 
tor meet on the first meridian. See painted 
Planisphere. The Fishes tied together by a flow- 
ing ribbon, making an angle at (a) alpha. The 
stars arc all small. On the black Planisphere, 
sec a, o, tt, r], p ribbon running north ; a, |, v, fi, 
C, e on the ecliptic ; 6, d, o> in ribbon running 
west; i, A, #, # in a square like the four corners 
of a house, y would make the peak or gable end, 
in the western Fish's eye. 

2. 8 «f A'RI-ES (the Bam). In the 
horns find a, (3, y of the 2nd, 3rd, and 4th mag- 
nitudes, and 5 in the tail. 

3. nK TAU'RUS (the Bull). In 
the face find a, ■&, a, 6, e, forming a triangle like 
a V or A, and called Hyades ; a and e the Bull's 
eyes. Both sides of the triangle extended would 
meet (3, C, in the ends of the horns. Pleiades 
(Ple-ya-dez), or seven stars, in the back of the 
neck, named after the seven daughters of Atlas, 
7] Al-cy'o-ne, Merope, Maia, Electra, Tayeta, 
Sterope, and Celena. Merope married a mortal, 
so she is dim among her sisters. 

I have a telescope, cased and rest or supporter, 
so small as all to go into my pocket; but it will 
show me 40 stars more plainly than I can count 
6 in the Plei'a-des with my unassisted eye; and 
which I can afford to sell for $25 ; or I have one 
a little larger, that shows me 60 stars in the 
Plei'a-des ; the stars in the Milky Way as thick as 
the beard stands on my face, and as distinctly 
separate as after shaving; Mercury, horned like 
the Moon at six days old; Venus, about the size 
of the Moon at ten days old ; Jupiter's belts and 
four moons ; Saturn's ring and moons, — good 
enough for any of my classes in Astronomy, — 
that I will sell for $50. 

4. s ^J GEM'I-NI (the Twins). In 
the heads find a, (3 ; e, £, A near the knees ; v, ft, 
v, v, £ near their feet ; in three lines nearly par- 
allel, a, e, fi; and 8, 6, £ y nearly parallel lines. 

x, i 

5. SIHK CAN'CER (the Crab). The 
stars all small, but can be found by the Plani- 
sphere. Making a triangle with y and 6 is e, 
looking something like a distant comet; but 
when seen through my $25 telescope, we see stars 
as thick as bees around the hive. It is called the 
Bee Hive. 

6. njj^^ LE'O (the Lion). In the 
fore-shoulder, a and ?; make the handle of tj, y, £, 
ft, e, A, the blade of the Sickle; j3, E, 6, •# make 
a large parallelogram. 



7. =2= fa VIR'GO (the Virgin). In 
the sheaf of wheat a ; ■&, y, -q on the left side and 
shoulder ; j3, v in the head ; z, : in the lower 
part of her skirt ; ft, f, 'a, k in and near her 
feet. Look them out on the painted Planis- 
phere ; and then take the black or natural one, 
to see how they look on the sky. 

8. nt j*j LI'BRA (the Scales). Find 
a t & 7, ■"■» which mako nearly a square. 

9. /4E SCOR'PI-0 (the Scorpion). 
v, 3, 5, 7r, p form the cuiwe, with a the body of a 
bow-kite, a, r, e, ft, £, tj, ■&, k, a, v the bobs : well 
worth looking up. 

10. ltf $r SAG-IT-TA'RI-US (the 
Archer), ip, g, t, fmake the bowl of an inverted 
dipper; a, u make the handle in the Milky Way: 
called the milk Dipper. 

11. s?^ CAP'RI-COR-NUS (the 
Goat), a, (3 in the horn ; y, 6 in the tail. 

12. X ^ A-QJJA'Rl-VS (the Water- 
Bearer). rf, £ y, tt in the urn make a Y. 

The Ecliptic is divided into 12 signs: count 
30° in each. Bring any minute we want to look 
at the sky to the day of the month. Inside the 
horizon see six of them ; note their position ; 
and go out and see them just as represented, by 
holding east towards the east horizon, south 
towards the south, with all the other points of 
the compass to correspond, the zenith overhead. 
Thus can six of the twelve signs be traced out 
on the clear sky. 



THE CONSTELLATIONS. 

PEG'A-SUS (the Winged Horse), a, 8, y, 
with a Al'phe-ratz, make the Square or Table; £ 
a, with a in head of AN-DROM'E-DA, d, [3, y 
a line of beatiful stars diagonally across the 
Squaro ; e, 6, tt near the breast ; 8, \i, v, called 
the Girdle; y in left foot; v in right foot; a, y, 
on the first meridian, point out the venial equi- 
nox, about as far below as they are apart. 

CAS-SI-O-PE'IA. a, (3, y form a triangle ; 
y, 6, e make another, — the two a W; a, 8 the 
feet ; y, k the seat ; d, e the back of the chair. 
Turn the horizon all around, being sure to keep 
the north always down towards the north hori- 
zon, the North Pole up, with the eye fixed upon 
the Chair as it revolves around the North Pole. 
Seen sometimes right side up, lying down on its 
back, upside down, feet up, and back down, and 
thrown down, with the back of the Chair up. 
Try it, as a beautiful puzzle for a scientific even- 
ing's entertainment. At any day outside find 
the hour and minute it will be in that position. 

CE'PHE-US, king of Ethiopia, husband to 
Cassiopeia, father of Andromeda, father-in-law 
of Perseus, make the Royal Family, a, 3, y, t 
form a large diamond; d, e, £ a little triangle in 
the crown and Milky Way. 

PER'SE-US with Ca'put Me-du'sa. v, y, a, 
6, c, ft, a look like a J or skate-runner; (3 is vari- 
able, it sometimes gets as small as p alongside 



OONSTELLATIONS. 



it, and returns to second magnitude in 3^ hours. 
Well worth looking up, and watching to see the 
change. 

UK'S A MA'JOR (the Great Bear), a, (3, 
the two hind wheels of the wagon, point towards 
the Polar Star; y, 6 the fore wheels; e, £ 
7] the three horses; called the Dipper, Butcher's 
Cleaver Ladle, Frying-Pan, Plough, Broad Axe, 
Bier and Three mourners, — some call them the 
Great Bear, not taking into consideration the 
other stars, c, {3 are called the Pointers, because 
they point one way toward the North Pole ; they 
point the other way toward the two, stars v, £ in 
the hindennost hind paw; p., A in the foremost 
hind paw; k, i in the fore paw, — three pairs of 
stars in a line. #, xp, v, h, o, curving in fore-leg, 
shoulder, neck, and head. Find them all, then 
look them out on the black Planisphere, that 
looks so natural, like the sky. When all are 
seen on the sky, and the very great space they 
occupy observed, we will not be disappointed that 
the word great was used, for he occupies a great 
space on the face of the heavens. It will astonish 
any one when first they find out how many 
different positions he is in during the year. By 
the Planisphere, it may be as easily as it is pleas- 
antly shown. Suppose we wish to look him up 
on the 4th of July, 9 o'clock; we then bring 9 
o'clock on the movable horizon to July 4th on 
the Planisphere. Ursa Major will be seen half 
way between the northwest and zenith, running 
toward the northwest, with his tail up. Run- 
ning down hill, the handle of the Dipper towards 
the zenith. By the middle of August, he will 
have made a very great change. Bring 9 o'clock 
to the 15th of August; see the paws a little 
above, and nearly parallel to the northwestern 
horizon. On Christmas night, he will appear 
reversed. Bring 9 o'clock evening to December 
25th, and find the paws not parallel, but nearly 
perpendicular to the horizon. The Bear not 
running down, but up, while the handle of the 
Dipper will not be up but down. Bring 9 o'clock 
evening to the 15^h of April, and find his hind 
paws nearlv overhead. 

UR'SA MFNOR (the Little Bear), a Polaris, 
or North Pole Star, in the end of the Little 
Bear's tail, is 1° 22' 4" from the Pole (or centre 
of the rivet) toward Cassiopeia. In the fore- 
shoulder find (3, y; near his hind quarter find 
C v ' the last four make the bowl of the Little 
Dipper; e, 6, a in the handle make the Butcher's 
Little Cleaver, Little Ladle, Little Frying-Pan, &c. 
The Pointers point out the Pole Star. Between 
it and the tail of the Great Bear will always be 
the Little Dipper. The Pole Star, (3, a, y beau- 
tifully mark out the Jirst meridian, the line from 
which Right Ascension begins. Look them up. 

AQUILA, Adwe-la (the Eagle), flying across 
the Milky Way; a, 0, y in the neck, in a row. 
No other three such stars, e, fin the tail; \i, 6 
in the wing. 

TAU-RUS PO-NI-A'TOW-SKI. lc,n,o,p 
in the face like a V, very near where the winter 
solstitial colure crosses the Equinoctial. 

DEL-PHI'NUS (the Dolphin), a, (3, y, 6, in 
the head, form a diamond called Job's Coffin ; e 
in the tail. 

LY'RA (the Harp), a, e, f, a small equilat- 
eral triangle, about as far on one side of the 



Milky Way as the Dolphin is on the other side. 

C YG'NUS (the Swan), with outspread wings, 
flying down the Milky Way. a, in the feet, is 
the top ; [3, in the head, the bottom or foot ; y, in 
the body, the centre ; 6, in the wing, one side ; s, 
in the other wing, the other side of a large cross, 
lying along the Milky Way. The Southern Cross, 
and those stars we cannot see in the United 
States, look for in the circle on the movable 
horizon. 

AU-RI'GA (the Wagoner), a, (3, y a triangle ; 
a, (3, ■& a triangle; e, £ r;, Three Kids, a triangle ; 
a, #, i, a triangle ; four small triangles make one 
large one, 6, (3, & one side, <5, a, Three Kids, and 
i the other side of the large triangle. 

O'RI-ON. a in right shoulder, y in left; A in 
head; d, e, fin waist, bands, three kings, yard; i] 
i» knee; t, c, » in the sword; « in skirt; rj, i, k 
English Ell; /3 in left foot ; y, c, ix, q, r, z in shield. 

LE'PUS (the Hare), a, [3, y, 6 look like a 
small parallelogram. 

CA'NIS MA'JOR (the Great Dog), a in the 
nose, the brightest fixed star seen in latitude 40° 
north; (3, fin the fore-paws; 6, e, tj, triangle. 

CA'NIS MI'NOR (the Little Dog), a, /3. 

HY'DRA (the Water Serpent). By the 
painted Planisphere, bring his nose setting in 
the west, while his tail will not yet be up to the 
meridian. It is Sf hours crossing the meridian. 
Look at any day outside, and see the hour and 
minute that will be the position of the stars on 
the sky. When learned, bring any minute to 
any day desired. The student may easily trace 
it out : d, e, f, ij in the head ; \9, neck ; a, heart ; 
k, A, //, v. Stars in the Cup, a, f3, 6, y, £ p, rj, i, 
$ ; then £, /?. Next the CRO W: a, j3, y, 6 form 
a large conspicuous trapezium ; then xp, y, u, tt. 
Look them up on the black Planisphere and sky. 

CO'MA BE-RE-NI'CES. Stars are ail 
small, reminding us of the Milky Way. 

BO-O'TES. a in the knee; ?/, r, v foot ; £, o, 
7T, $ in right kg and foot ; e, p waist ; (3 head ; 
y left shoulder; 6 right shoulder. Look them 
all out on the black Planisphere, a figure 2. 

CO-RO'NA (the Northern Crown). #, (3, a, 
y, 6, e in a semi-circle, or the curve; 6 in 
Bootes, the end of the handle of a Sickle. 

OPH-I-U'CHUS (the Serpent Bearer), a in 
the head ; /?, y on the right shoulder. The Ser- 
pent is beautifully marked out by stars j3, y, x, l , 
p, making an hour-glass, or X, in the head ; 6, 
7l, a, e, p., 6, e, £, r\, v, £, v, r], ■&. 

HER'CU-LES. a in head ; /?, y right shoul- 
der ; h, n arm and hand ; 6, \ fi, £ in left arm ; 
o in hand ; $, e in waist ; u the star toward which f 
the Sun is said to be moving; tt, e, p left leg; 
tj, o, t right leg ; i, k left foot over the head of 

DRA'CO (the Dragon), p in nose ; (3, y head ; 
f, v lower jaw. tt, t, x 2nd coil. $, 7/ 3-rd coil. 
t^, i. a 4th coil, i, k, 1. 



The Movable Planisphere is to Astrono- 
my the same as a Map is to Geography, or to 
the clear sky what the Directory is to a City. It 
is the size of a 10-inch Celestial Globe, and as 
much better as it is cheaper. Of two kinds; one 
beautifully painted, the other as much like the 
sky as possible : Stars white on a deep blue-black 
ground. Both make a complete set. Sold or 
sent by mail on receipt of $6. 



PROBLEMS FOR THE MOVABLE PLANISPHERES. 



To determine on any given day when the Star 
will rise. 

Rule 1 . Bring the eastern horizon to the cen- 
tre of the given Star. At the given day, on the 
circumference of the Planisphere, may be seen 
on the movable horizon the time when the Star 
is rising. 

When will Reg'u-lus rise Jan. 10th 1 ? ans. 
8 o'clock, evening. 

When will An-ta'res rise May 6th 1 ? ans. 
4 minutes after 9 o'clock, evening. 

When will Al-dWa-ran rise Sept. 22nd? 
ans. &| o'clock, evening. 

To determine on any given day when a Star will 
set. 

Rule 2. Bring the western horizon to the cen- 
tre of the Star. At the given day, on the cir- 
cumference of the Planisphere, may be seen on 
the movable horizon the time when the Star 
will set. 

When wity Al-deb'a-ran set on the 27th of 
April? ans. 9 o'clock, evening. 

When will Reg'u-lus set on the 4th of July ? 
ans. 10 minutes before 10 o'clock, evening. 

When will An-ta'rcs set on the 28th of Aug.? 
ans. lOh. 9m., evening. 

To determine on any given day when a Star will 
arrive at the Meridian. 

Rule 3. Bring the graduated Meridian to the 
centre of the Star. At the given day, on the 
circumference of the Planisphere, may be seen 
on the movable horizon the time the Star will 
arrive at the Meridian. 

When will Al-deb'a-ran arrive at the Meridi- 
an Feb. 11th? ans. 7 o'clock, evening. 

When will Reg'u-lus south on" the 17th of 
March? ans. 20 minutes past 10 o'clock in 
the evening. 

When will An-ta'res come to the Meridian, 
or south, on the 26th of June? ans. 10 
o'clock, evening. 

The day of the month, the hour, and minute being 
given, to find the Stars rising, setting, on the Me- 
ridian, or in any other part of the firmament. 

Rule 4. Bring the given hour and minute on 
the circumference of the movable horizon to the 
given day of the month on the circumference of 
the Planisphere ; hold the Zenith overhead, with 
South horizon toward the South, North toward 
the North, East toward the East, West toward 
the West. On the Planisphere read the names 
of the Constellations and chief stars, each in its 
proper position, — the stars rising in the East, 
tJx>se setting in the West horizon; by which 
simple arrangement can be seen the stars in any 
part of the sky, at all times sufficiently accurate 
for most practical purposes. 

What Constellations will be on the Meridian 
Feb. 10th, 8 o'clock, evening? ans. Dove, 
Hare, Orion, Cam'el-o-pard, Little Bear, * and 
Dragon, and Wagoner in the Zenith. 

What important line will be on the Meridian 
at 10 o'clock, Oct. 21st? ans. the First 
Meridian, marked out by the four prominent 
stars, Al'ge-nib, Al'phe-ratz, Caph, and North 
Polar Star. Find them on the Planispheres. 



What star will rise near the northeast at 9 
o'clock, evening, October 24th? ans. Cas'tor, 
in the Twins. 

What star will be setting near west-northwest 
at 10 o'clock, evening, April 11th? ans. Al- 
deb'a-ran. 

When does "A-ri-e'tes south at lOh. lm. after- 
noon ? " ans. Nov. 20th. 

To determine the time of rising or setting of the 
Sun on any day. 

Rule 5. Bring the Eastern horizon, if rising, 
or the Western horizon, if setting, to the given 
day of the month marked on the Ecliptic. At 
the same day on the circumference of the Plani- 
sphere is the time, on the circumference of the 
movable horizon. 

What time does the Sun rise, and set, on the 
10th of May, in latitude 40° North? ans, 
Sun rises 8 minutes before 5 o'clock in the morn- 
ing, and sets 2 minutes after 7 o'clock in the 
evening. 

What time will the Sun rise and set on the 
21st of June? ans. rises 4h. 35m., and sets 
7h. 32m. What time will the Sun rise and set 
on the 22nd day of Dec? ans. rises 7h. 
25m., and sets 4h. 29m. 

To find the Azimuth and Amplitude of the Sun 
when rising or setting on any given day. 

Rule 6. If rising, bring the Eastern, or if set- 
ting, the Western horizon to the given day on 
the Ecliptic; note the points of the compass, 
and count on the horizon the degrees to the 
North or South for the Azimuth, and to the East 
or West for the Amplitude. At the same day, 
outside, may be read the minute at which cither 
occurs. 

What is the Sun's azimuth and amplitude 
when rising, or setting, on the 10th of May? 
ans. azimuth 67°, amplitude 23°. 

What is hi* azimuth and amplitude when 
rising, or setting, on the 2 lit of June? ans. 
azimuth 58°, amplitude 32°. 

What is his azimuth and amplitude when 
rising, or setting, on the 22nd of Dec? ans. 
azimuth 58°, amplitude 32°. 

Altitude Scale, by H. M. Parkhuest. 

To find the Altitude or Zenith distance of a Star. 

Rule 7. Set the horizon for the given day 
and hour. Lay a straight-edge en the zenith 
passing through the Star, and cutting the hori- 
zon in two opposite points. Observe the point 
of the compass toward the north, through which 
the line passes ; measuring from the Star to the 
horizon (or zenith), we have the altitude (or 
zenith distance respectively) to be taken from 
the Altitude Scale upon the line from the centre, 
marked i Star/ toward the point of the compass 
already noted. 

What is the altitude of Spica June 16th, at 
10 o'clock, evening? ans. 31°. 

.What is the zenith distance of Dubhe at 9 
o'clock, May 26th? ans. 32°. 

What is the altitude of Deneb at 1 1 o'clock, 
•evening, April 20th ? ans. 15°. 

What is the zenith distance of Arcturus May 
29th, at 9 o'clock, evening ? ans. 25°. 



PROBLEMS FOB, THE MOVABLE PLANISPHERES. 



When or where can Mercury be seen t Only 
at or near its greatest elongation. 

Rule 8. Find in the almanac the gr. Elong. 
Then find on the Ecliptic, on the Planisphere, 
the same day (the Sun's place at noon); from 
that day count the number of degrees on the 
Ecliptic to the place of Mercury on the Plani- 
sphere, East, if evening star; West, if morn- 
ing star. By Rule 5 see the position at sunrise 
or sunset. By Rule 7 find its altitude. " May 
4th, 9 gr. Elong. E. 45° 32'" will be 1° in 
Gemini. "May 20th, £ gr. Elong. E. 22° 
34' J " will be 22° in Taurus 20° high at sunset, 
seen as evening star. 

Among all the stars visible on a clear evening, 
which is Venus, Jupiter, or any other planet? 

Rule 9. Find in the almanac the time the 
given planet will rise, south, or set, which time 
also find on the circumference of the movable 
horizon, and bring it to the same day of the 
month found on the outer circle of the Plani- 
sphere. If rising, the place of the planet will 
be where the Eastern horizon meets the Ec- 
liptic. If southing, where the Meridian meets 
the Ecliptic. If setting, where the Western 
horizon meets the Ecliptic. " May 2d Venus 
sets lOh. 48m. Aft.," 2° in Gem'in-i. "May 
13th, Jupiter rises 7hl8ra. Aft.," 26° in Libra. 

To find the Moon's place in the Zodiac three 
times any given day. 

Rule 10. Find in the almanac four columns ; 
the Moon rises, or sets, or souths can be found 
by Rule 9. Moon's constellations in one col- 
umn, and in the other the degrees. Find on 
the Planisphere the Ecliptic, and the Constel- 
lation, then count in it the given number of 
degrees for the Moon's place at noon. "May 
31st, Moon sets lh. 8m. Morn.," 26° in Le'o. 
At noon 29° in <%z$l souths 7h. 29m., After- 
noon, 2° in Vir'go. 

Given in the almanac: Conjunction, or near 
together, rf 0° apart; Quadrature, Q90°; Trine, 
A 120°; Opposition, <p 180° from the Sun ©; 
to locate either on the Planisphere or sky. 

Rule 11. Find the day of the month on the 
Ecliptic (Sun's place), from which count the 
number of degrees to the planet's place, on 
the Planisphere, then see it in the sky. " May 
17th, cP Qj. O" fo»nd 27° in Li'bra. "May 
28th, Q 1? 0" found 7° in A-qua'ri-us. 

When I graduated I could calculate an 
Almanac, but not name a star on the clear sky ; 
if my Professors knew, they never taught me. 
Twenty-one years spare time improved, pro- 
duced my Movable Planisphere. It takes a 
long time for one to enquire, where do you 
live? where do you live? and where do you 
live? to make a directory. When correctly 
made, how easy to find the one we want? So is 
this a Directory of the Sky, to Astronomy 
what a map is to Geography. With them I 
can teach more on the sky in one hour than I 
learned in a year without their use. These 
explanations are intended to enable the intel- 
ligent teacher to do so too. Send Post-Ofiice 
Order of $6.00 to Henry Whitall, 512 Arch 



Street, Philadelphia, Pa., and by return mail 
get a full set. 

The first Telescope I bought, which cost 
my Father $125.00, was so large it was neces- 
sary for me to carry out the stand, set it up, 
then go back, unlock the box and carry the 
Telescope and put it in place, then go" once 
more for the eye-piece and handles. 

I now have a small portable Telescope, I 
can put into my pocket, stand and all ; carry 
with me to my classes without any incon- 
venience, that will show me as much and as 
well as my first one, which I can send by 
express, C. O. D., for $50.00.^ With it I can 
see three stars in the Trapezium of Orion. 

A man who shows his Telescope in the 
streets, and has several sons at the same busi- 
ness, told me he had just sold his large glass for 
$350.00, cash, that would show four stars in 
the Trapezium of Orion, — a great test. 

A noted optician of much repute, asked me 
to test a Telescope he had sold for $600.00, 
cash, before it left the store. I met the opti- 
cian and clerk by appointment ; the clerk gave 
me a part, gave the owner a part, and he 
shouldered up the largest load for himself to 
carry to the test place. I saw five stars in 
the Trapezium of Orion. We tried several 
others; the owner was delighted; he did not 
ask for a comparison, so I did not intrude my 
Telescope on him. We carried the Telescope 
all back, the clerk left with me, and I put my 
little glass on the same tests, when the clerk 
said "he would rather have that than the larger 
one; some had more money than knowledge." 

My friend, an Amateur Astronomer, in 
Wall Street, has a Telescope that, when very 
favorable and clear weather, will faintly show 
the sixth star in the Trapezium of Orion. It 
cost over $1000.00. 

For $50.00, 1 can see three stars ; for $350.00, 
see four stars; for $600.00, see five stars; for 
$1000.00, see the sixth star faintly. My lit- 
tle Telescope shows me enough for my As- 
tronomy classes easily to understand all the 
pictures shown by the largest Telescopes. 

I showed my Telescope to a celebrated 
maker to know if i could make a business 
through him; he told me he would charge 
$90.00 for making one as good as mine, but 
would let me have it for $85.00. 

The first Telescope I bought cost my Father 
$75.00 more than I can now sell as good a one 
for, and cost me many years expense of a, 
horse to haul it around, or two assistants, or 
for me to go three times to carry my Telescope 
to the place to show it to my classes of As- 
tronomv, but not see any more than with my 
$50.00 Pocket Telescope. 

Sent bv Express, C. O. D. Address, Henry 
Whitall, "512 Arch Street, Philadelphia, Pa. 

"If I could not get another Movable Plani- 
sphere, I would not sell mine for fifty dollars. 
Geo. PL Chace, Lynn, Mass. 

"Should be in every book-store for sale, and 
in every family and school for use." — Telegraph. 



PROBLEMS FOR THE MOVABLE PLANISPHERES. 



To find the time twilight will begin or end for any 
given day in the year. 

Rule 12. Brings the twilight line to the given 
day on the Ecliptic ; at the same day, outside, 
read the minute it will begin or end. 

When will twilight end Jan. 1st? Ans. 6h. 
23m., evening. When Feb. 22nd? Ans. 7h. 
14m., evening. When May 20th? Ans. 9h. 
8m., evening. When July 4th? Ans. 9h. 32m., 
evening. 

To find the duration of Twilight. 

Rule 13. By Rule 5, find the time the Sun 
will rise or set; by Rule 12, find the time twi- 
light will begin or end. The duration of twilight 
in the morning is from twilight begins to sun- 
rise; and, evening, from sunset to twilight ends. 

What is the duration of twilight March 20th ? 
Ans. About 1^ hours. What is the duration 
of twilight June 21st? Ans. About 2h. 10m. 

To determine the course and position of the Milky 
Way at any given time. 

Rule 14. Bring the given minute on the cir- 
cumference of the movable horizon to the given 
day on the circumference of the Planisphere. 
The points of the horizon and graduated Me- 
ridian over the Milky Way will indicate its 
course and position. 

What is the position of the Milky Way 14m. 
past 9 o'clock, evening, Jan. 1st? Ans. From 
S.E., in Zenith, to N.W. What is the course 
and position of the Milky Way at 10 o'clock, 
evening, Sept. 6th ? Ans. From N. E., in Ze- 
nith, to S.W. What is the position of the 
Milky Way Sh. 21m., evening, Nov. 25th ? Ans. 
From East, in 60° North Declination to West 
horizon. What is the position of the Milky 
Way at 10 o'clock, on the 2nd of May? Ans. 
So near the East, West, and North horizon as 
not to be seen. 

Consider B kiddle's astronomy. 
the Vernal E- Fig. 1. 

quinox, A the 
Autumnal E- 
quinox, C the 
North Pole. B, 
D,E,F,A, 180° 
of the Equinoc- 
tial; 180° more 
will complete 
the circle of 
3G0°. C B will then represent the first meridi- 
an, where the right ascension begins. C D, 
C E, C F, C A, the meridian that may as easily 
be moved to any other place to mark the right 
ascension of any heavenly body. 

To find the Bight Ascension and Declination of a 
heavenly body. 

Rule 15. Bring the meridian to the centre of 
the star. Where it meets the equinoctial, read 
the degrees of Right Ascension ; at the arrow out- 
side, near March 22nd, read the hours and min- 
utes of Right Ascension. Over the star, on the 
meridian, read tin Declination. 

What is the right aseension and declination 
of j3 Algol, the variable star in Medusa's head? 
Ans. 45°, or three hours right ascension, 40° 
north declination. What is the right ascension 
and declination of Fomalhaut? Ans. 242^°, 
or 22h. 51m. right ascension; declination, 30^-° 
south. 




To find the Declination and Right Ascension of 
the Sun any day in the year. 

Rule 16. Bring the Meridian to the given 
day on the Ecliptic; over it, on the Meridian, 
read the Declination. Where the Meridian meets 
the Equinoctial, read the degrees; and at the 
arrow by March 22nd, outside, read the hours 
and minutes of Right Ascension. 

What is the right ascension and declination 
of the Sun March 20th? Ans. 0°. What 
June 21st? Airs. 90°, or 6h. right ascension, 
23° 27' north declination. What Dec. 21st? 
Ans. 270°, or 18h. right ascension, 23° 27' 
south declination. 

Equation of Time. 

The Planisphere will illustrate each cause sepa- 
rately, as well as combine .both causes, and show 
the Sun fast or slow for any day. If this were 
its only use, when rightly understood, all classes 
of Astronomy would us« it when they want to 
thoroughly understand Equation of Time. 

The Equation of Time, iohen the unequal motion 
of the Earth only is considered. 

Rule 17. lind July on the Ecliptic of the 
Planisphere, lay a straight piece of paper on 
July 1st, and make a mark, and another at July 
10th, another at July 20th, another at July 31st. 
Lay first mark at Jan. 1st, on the Ecliptic, make 
a mark at Jan. 10th, another at Jan. 20th, and 
another at Jan. 31st. It is remarkable how 
nearly it will compare with the works on As- 
tronomy having a figure showing that the Radius 
Vector describes equal areas in equal times. 

More accurately by H. M. Parkiiurst. 

Rule 18. By Rule 16, find the right ascen- 
sion of the Sun July 1st and 31st So compare 
the motion of the Sun in right ascension for 
July, and see how much farther the Sun moves 
in Jan.; or so compare any other equal number 
of days. 

To determine the Equation of Time on any given 
day, the obliquity of the Ecliptic only considered. 

Rule 19. Bring the graduated Meridian to 
the given day on the Ecliptic ; the degree, count- 
ed from the Vernal Equinox, will indicate the 
longitude of the Sun. At the same time it will 
indicate on the Equinoctial his right ascension ; 
the difference of right ascension and longitude 
is the Equation of Time. If the longitude is 
greater than right ascension, the Sun is fast, and 
if it is less, the Sun is slow, four minutes to a 
degree. 

Is the Sun fast or slow on the 21th of May? 
Ans. 2° difference, or 8 minutes fast. What is 
the Equation of Time June 21st? Ans. 0. 
Longitude and right ascension of the Sun agree. 
What is the equation of time July 31 ? Ans. 
10 minutes slow. 

Equation of Time: to find how much the Sun is 
fast or slow, both causes combined. 

Rule 20. Bring the Meridian to the given 
day on the Ecliptic; at the same day on the 
outer circle will be the time the Sun is on the 
Meridian; if before 12 o'clock, the Sun is fast, 
if after 12 o'clock, the Sun is slow. 

Bring the Meridian to Nov. 10th, on the Eclip- 
tic; at that date, outside, will be found llh. 
44m., the Sun being 16 minutes fast. 

Is the Sun fast or slow on the 31st of Oct.? 
Ans. Fast, 16 minutes. 



PROBLEMS FOR THE MOVABLE PLANISPHERES. 



Is the Sun fast or slow on the 24th of Dec? 
Ans. Neither, Is the Sun fast or slow on the 
31st of Jan.? Ans. Slow, 14 minutes. 

To convert Mean Clock Time into Siderial Clock 
Time. 

Rule 21. Bring the given Mean Clock Time 
on the circumference of the movable horizon to 
the given day on the circumference of the Plani- 
sphere; the minute at the point of the arrow, 
on the circumference of the movable horizon, 
will indicate true Siderial Time. 

At 33 minutes past 9 o'clock p.m. on the 4th 
of July, what is the siderial clock time? Ans. 
16h. 25^m. At one minute past 11 o'clock p.m., 
Sept. 18th, what is the siderial clock time? Ans. 
22h. 53m. 10s. 

To convert Siderial Clock Time into Mean Clock 
Time. 

Rule 22. Bring the Siderial Clock Time to the 
arrow at March 22, outside ; at the day of the 
month, read the Mean Clock Time on the mov- 
able horizon. When the siderial clock is 19h. 
44m. 35s., Altair will be on the Meridian ; what 
will be the Mean Clock Time? Ans. Aug. 10th, 
lOh. 26m. When the siderial clock is 22h. 
50m. 37s., Fomalhaut will be on the Meridian, 
its right ascension : what is the clock time ? 
Ans. 9k. 12m. on the 15th of Oct. 

To find the difference between a Siderial and a 
Solar Day. 

Rule 23. Bring the graduated Meridian to 
any given day on the Ecliptic. From the same 
day, outside, count the number of minutes to 
the next day for the difference between a Siderial 
and a Solar Day. 

What is the difference of time between the 
siderial and solar day Oct. 14th? Ans. Nearly 
4 minutes. Try any other day for the same 
answer. 

T~ find the length of any given-, day. 

Rule 24. Bring the western horizon to the 
given day on the Ecliptic ; the minute on the cir- 
cumference of the movable horizon, at the same 
given day on the circumference of the Plani- 
sphere, is the time the Sun will set, which time 
if doubled is the required length of the day. 

If greater accuracy is required, add to the 
time of sunset the equation of time, if the Sun 
is fast, or subtract it if the Sun is slow, before 
doubling. 

What is the length of the 21st of June ? Ans. 
15h. 8m. What is the length of Oct. 30th? 
Ans. The Sun sets at 5h. 0m.; adding 16m.; 
the equation of time, and then doubling, the 
dav's length is lOh. 32m. What is the length 
of "Feb. 14th? Ans. The Sun sets at 5h. 31m. 
Subtract 14m., and then doubling, the day's 
length is lOh. 34m. 

To tell the length of a Siderial Day. 

Rule 25. Bring the Meridian to the centre 
of a Star, and note the time. Turn the horizon 
until the Star sets, and rises, and comes on the 
Meridian again. Note the time for a Siderial 
day, the revolution of the Sun upon its axis. 

To find the length of a Solar Day, or from the 
Sun crossing the Meridian any day to crossing it 
the next day. 

Rule 26. Bring the graduated Meridian to 
the day of the month on the Ecliptic ; at the 
same day, outside, see the time on the circum- 



ference of the movable horizon. Then turn the 
western horizon up to the day of the month, and 
bring it to the eastern horizon, when it will rep- 
resent the next morn; and bring the next day 
to the Meridian, and see at the second day on 
tho movable horizon the time the Sun comes to 
the Meridian, the time of the Sun's being on 
the Meridian two successive days. 

To find the length of a Lunar Day. 

Rule 27. By Rule 10th, locate the Moon on 
any day. Then bring the Moon's place on the 
Ecliptic to the Meridian; at the same day, out- 
side, note the time on the circumference of the 
movable horizon. Bring the Moon setting, and 
by Rule 10th locate the Moon for the acxt day, 
and bring its place onto the Meridian, at which 
day, outside, on the movable horizon, noto the 
time for a Lunar Day to us. 

When tlie Sun runs highest in Slimmer, the full 
Moon runs lowest. 

Rule 28. Bring near the N.W. by W. part of 
the movable horizon to June 21st on the Eclip- 
tic for the Sun setting at his most northern dec- 
lination. Should the Moon full on that day, 
she will be seen rising near the S.E. by E. hori- 
zon at her greatest southern declination. To 
make this practical, see in the almanac when the 
Moon fulls nearest June 21st, and by Rule 10 
locate the Moon, and bring the day of the month 
on the Ecliptic to the western horizon, and see 
how low the full Moon's place is. Thus June 
10, 1873, the Moon fulls; at noon she is 18° in 
the Scorpion. It will be seen that while the 
Sun is setting near the N.W. by W., the 18° of 
Scorpio will be rising near the S.E. by E. 

When the Sun runs lowest in Winter, the full 
Moon runs highest. 

Rule 29. Bring the S.W. by W. horizon to 
Dec. 21st on the Ecliptic for the Sun setting at 
his greatest southern declination. Should the 
Moon full on that day, she will be seen rising 
near the N.E. by E. at her greatest northern dec- 
lination. Look in the almanac, and see when 
the Moon fulls nearest Dec. 21st, and by Rule 
10 find the Moon's place, then apply this rule. 

Dec. 14, 1872, the Moon full, and" was at noon 
21° in the Bull. While the Sun sets near the 
S.W. by W., see 21° in the Bull rising near the , 
N.E. by E. 

To find the Azimuth and Amplitude of a Star 
when rising en' setting any given day in latitude 40° 
NortJi. 

Rule 30. Find the given Star on the Plani- 
sphere. Bring the eastern horizon, if for rising, 
or the western horizon, if for setting, to the 
given Star. Count the number of degrees be- 
tween the Star and south or north horizon for 
Azimuth. The degrees between the Star and 
east or west will be the Amplitude. Read the 
time it will occur at the day of the month out- 
side. 

When will Sirius, the Dog Star, rise, set, and 
what is its azimuth and amplitude when rising 
or setting ? Ans. Rises at 9 o'clock, Nov. 29th, 
and sets at 9 o'clock, evening-, May 1st; azi- 
muth 67^°, amplitude 22£°. When will.Arctu- 
rus rise and set, and what is its azimuth and 
amplitude when rising and setting ? Ans. Rises 
9 o'clock, Feb. 20th, and sets at 9 o'clock, even- 
ing, Sept. 24th; azimuth 65°, amplitude 25°. 



10 



PROBLEMS FOR THE MOVABLE PLANISPHERES. 



Wm. Wiley oftDetrcit, Mich., very acceptably 
proposes 

2 o obtain the correct Vertical Line for every ten 
degrees of Azimuth. 

Rule 31. The Meridian is a straight line. 
Ten degrees on either side the Vertical Line -will 
be the arc of a circle whose radius is 11.38 inch- 
es, -which arc lay on the Zenith and ten degrees 
Azimuth, and the space between divide into 90° 
for Altitude or Zenith Distance. For 20° Azi- 
muth the radius will be 7.65 inches; for 30°, 
6.25 inches; for 40°, 5.55 inches; for 45°, 5.45 
inches; for 50°, 5.37 inches; for 60°, 5.25 inch- 
es; for 70°, 5.15 inches; for 80°, 5.02 inches; 
for 90°, Prime Vertical, 5 inches, — with the con- 
cavity always towards the North. 

To toll the minute in the day the Sun will be due 
East, West, Southeast, or Southwest at any place 
in or near Latitude 40° North. 

Rule 32. Lay the appropriate arc by Rule 
31 on 40° North Declination and the desired 
point of the compass. Turn the horizon until 
the arc meets the desired day on the Ecliptic. 
At the same day, outside, read the minute the 
Sun will be seen in that point of the compass of 
the horizon. 

When will the Sun be due east in New York 
June 21st? Ans. 8h. 7m., morning. When 
will the Sun be southeast in New York June 
21st? Ans. 1 Oh. 45m., morning. When will 
the Sun be seen Southwest in Philadelphia Dec. 
21st? Ans. 3h. 30m., afternoon. 

To find the Azimuth, Amplitude, Zenith Dis- 
tance, Vertical Circle 'of the Sttn, Moon, Stars, or 
Planets at any given time. 

Rule 33. The Sun's place is where the day 
of the mouth is on the Ecliptic. The fixed Stars 
are marked on the Planisphere. The Planets 
may bc*located by the almanac and Problems 
8th or 9th. Bring the given time to the day of 
the month. Lay the proper arc by Rule 31 on 
the Zenith to pass through the Star, Sun, or 
Planet's place to meet the Horizon for the Verti- 
cal Arc. Count the degrees on the Horizon from 
the North or (South to the Vertical Arc for the 
Azimuth. From the East or West to the Verti- 
cal Arc for the Amplitude. 

Find the Altitude and Zenith Distance by Rule 7. 

What is the azimuth, amplitude, zenith dis- 
tance, and altitude of the Sun at 10 o'clock on 
the morning of June 21st. Ans. Azimuth, 62°, 
amplitude 28°, zenith distance 30°, altitude 60°. 

To find when the Sun will shine on the North 
side of a House when lie rises or sets, and at noon 
shine on the South side. 

Rule 34. Our position is under the Zenith; 
the latitude counted on the Meridian whence we 
look. Should it be at or near 40° North, find 
on the Ecliptic the day of the month (the Sun's 
place at noon ) , and bring it to the East horizon 
for rising, or West horizon for setting. If North 
of East or West, the Sun will shine on the 
North side of the House, or if South, on the 
South side. Then bring the Meridian to the 
day of the month on the Ecliptic, when above 
24° North latitude, the Sun will be South, and 
shine on the South side of the House. 

To find how long the Sun will shine on the North 
side of the House on any given day, and how long 
on the South side. 



Rule 35. Lay the Prime Vertical, obtained by 
Rule 31, on the Zenith and East for after sun-ris- 
ing, or West for before sun-setting. The Sun will 
shine on the North side of the House from rising 
to the Prime Vertical, and shine on the South 
side until he arrives at the western Prime Verti- 
cal, then on the North side until setting. 

How long will the Sun shine on the north 
side, and how long on the south side of a house 
on Jan. 21st, whose sides arc placed to range on 
the cardinal points? Ans. 3h. 33m. in the 
morning; shines on the south side 8h. 8m.; and 
on the north side 3h. 33m. in the evening; 7h. 
6m. on north side; 8h. 8m. on south side; the 
day 15h. 14m. long. 

To determine the place of a heavenly body on the 
Planisphere at any given time, tlie Right Ascension 
and Declination being given. 

Rule 36. Bring the given time of Right 
Ascension, found on the outer circumference of 
the movable horizon, to the arrow, at March 
22nd, outside. At the graduated meridian on 
the Equinoctial will be the degrees of Right 
Ascension. From that point count the number 
of degrees of Declination of the object on this 
Meridian; that number will indicate its placeon 
the Planisphere. 

Where is the Sun's place on the Planisphere, 
— his right ascension, declination, longitude, and 
latitude being ? Ans. At the vernal equinox, 
or first point Pisces (one sign from Aries), where 
they all begin. Where is the place of Eomal- 
haut on the Planisphere, — the right ascension 
being 22h. 50m. 37s., declination 30° 17' south? 
Ans. In the eye of the Southern Pish. What 
is the place of Saturn on the Planisphere on the 
4th of July, 1873, — the right ascension being 
20h. 11m. 51s., and declination 20° 18' south? 
Ans. 30° in the Archer. 

To convert Degrees of Right Ascension into Time. 

Rule 37. Ei'nd the given number of degrees 
of Right Ascension on the Equinoctial. Bring 
the Graduated Meridian to that number; the 
arrow by March 22nd., outside, will point to the 
minute of Time on the circumference of the 
movable horizon that corresponds to the given 
numher of degrees. 

275° are how many hours and minutes of 
right ascension ? Ans. 18h. 20m. 

To convert Time into Degrees of Right Ascension. 

Rule 38. Bring the given minute of Time on 
the circumference of the movable horizon to the 
arrow. The number of degrees of Right Ascen- 
sion, corresponding to this time, will be found 
where the Graduated Meridian crosses the Equi- 
noctial. 

The right ascension of Al-deb'a-ran is 4h.28m.; 
what is it in degrees? Ans. 67°. The Right 
Ascension of Regulus is lOh. lm.; what is it in 
degrees? Ans. 150^°. Antarcs is 16h. 21m. 
right ascension; what is it in degrees? Ans. 
245i°. 

To determine the time when a true Meridian Line 
can be obtained on any given day. 

Rule 39. Bring lh. 12m. afternoon to the 
arrow ; the minute on the circumference of the 
movable horizon, at the given day on the gradu- 
ated circumference of the Planisphere, indicates 
the time when the North Star is in the position 
to indicate a True Meridian. In six hours from 



PROBLEMS FOR THE MOVABLE PLANISPHERES. 



11 



this time the North Star will be at its greatest 
western elongation. Six hours later it will be 
on the Meridian below the Pole. Six hours 
later it will be at its greatest elongation East. 

When can iv« get a meridian line on the 10th 
of May? Ans. 2m. before 10 o'clock, evening. 

When can we get a meridian line on the 23rd 
of Nov? Ans. 9h. lm., evening. 

Given the Latitude of the Ship and Day of the 
Month, to find the Meridian Altitude of the Sun. 

Rule 40. Find on the Meridian the degrees 
of Latitude of the place, and call it Zenith. 
Bring the Meridian to the given day on the 
Ecliptic. Count the degrees between it and the 
Zenith for the Zenith distance, which taken from 
90° will be the Meridian Altitude. 

What is the Sun's meridian altitude to-day, 
Sept. 15th, at noon, in New York? Ans. 52^°. 

A ship at sea, 60° south latitude, on Christ- 
mas, wants to know the Sun's meridian altitude. 
Ans. 53 j° above north horizon. A ship at sea, 
60° north latitude, on Christmas, wants to know 
the Sun's meridian altitude. Ans. 6j° above 
south horizon. 

Given the Meridian Altitude of the Sun on any 
day, to find the Latitude of the Ship. 

Rule 41. Subtract the Altitude of the Sun, 
when on the Meridian, from 90° for the Zenith 
Distance. Bring the Meridian to the given day 
on the Ecliptic, from which count the Zenith 
Distance to the Latitude of the place. 

The meridian altitude of the Sun July 4th is 
72^°: what is the place? Ans. New York, or 
latitude 40j north, if seen above the south ; or 
5^- north latitude, if seen above the north horizon. 

A ship at sea measures the meridian altitude 
of the Sun 30° on Feb. 22nd: what is the ship's 
latitude? Ans. If above north horizon, the 
ship is 70° south ; if above the south, 50° north 
latitude. 

Given the Latitude of a place in the Torrid 
Zone, to tell the days the Sun will be Vertical. 

Rule 42. Count from over the Equinoctial 
the given number of degrees to the North or 
South on the Meridian. Turn the Meridian so 
that the given number meets the Ecliptic, at 
which point of meeting read the required day. 
If the number meets the Ecliptic at two points 
at each, read the day the Sun is Vertical. 

When will the Sun be vertical to all those 
places that have no altitude, or are on the Equa- 
tor? Ans. March 20th and Sept. 22nd. When 
will the Sun be vertical to San Jose, or all places 
10° north latitude? Ans. April 15th and Aug. 
27th. 

To determine the Latitude and Longitude of a 
Ship at Sea by a Star visible in the Zenith. 

Rule 43. Bring the Graduated Meridian to 
the Star. If the Star is in the Zenith, its Dec- 
lination, as found on this Meridian, is the Lati- 
tude of the Ship. To determine the Longitude, we 
find the Ship's time on the circumference of the 
movable horizon, at the given day marked on the 
graduated circumference of the Planisphere. 
The difference between it and chronometer time, 
converted into degrees, will give the Ship's Lon- 
gitude. 

If Sir'i-us is in the zenith on the 22nd of Feb., 
what is the ship's time and latitude ? Ans. 8h. 
31m., evening, and 16^° south. If An-ta'res is 



in the zenith on the 4th of July, what is the 
ship's time and latitude? Ans. 9h. 31m. 45s. 
p.m. and 26° south latitude. 

If Al-deb'a-ran is in the zenith on the 25th day 
of December, what is the ship's time and lati- 
tude? Ans. lOh. 13m. 30s. p.m., and 16^ north 
latitude. 

To find the Latitude and Longitude of a Ship 
at Sea by any Star on the Meridian, not in -the 
2Zenith, but whose zenith distance is detennined. 

I. When the Star and Ship are North of the 
Equinoctial, and the Star North of the Ship. 

Rule 44. Bring the Graduated Meridian to 
the Star. Find its Declination in degrees, on 
this Meridian, from which subtract the zenith 
distance. The remainder is the latitude of the 
Ship. By Rule 43 find the Ship's longitude. 

If the zenith distance of Ca-pel'la on the me- 
ridian is 6° on the 25th of Dec, what is the 
ship's time and latitude? Ans. lOh. 50m., even- 
ing, and 40° north latitude. If Al-deb'a-ran is 
on the meridian, and 6^° north of the ship on 
the 25th of Dec, what is the ship's time and 
latitude? Ans. lOh. 12m. p.m., and 10° north 
latitude. 

II. When the Star and Ship arc South of the 
Equinoctial, and the Ship South of the Star. 

Rule 45. Bring the Graduated Meridian to 
the Star. Find its Declination in degrees, on 
this Meridian, to which add the zenith distance. 
The sum is the latitude of the Ship. By Rule 
43 find the Ship's Longitude. 

If Sir'i-us is on the meridian, and 3G^° north, 
on Feb. 22nd, what is the chip's time and lati- 
tude? Ans. 8h. 30^m., evening, and 53° south 
latitude. Spi'ca is on the meridian, and 30^° 
north of the zenith March 17th: what is the 
ship's time and latitude ? Ans. lh. 38m., morn- 
ing, and 41° south latitude. 

III. When Hie Ship is North and the Star 
South of the Equinoctial, and vice versa. 

Rule 46. Bring the Graduated Meridian to 
the Star. Subtract the Declination of the Star 
from the zenith distance, the remainder will be 
the Ship's Latitude. By Rule 4-3 find the Ship's 
Longitude. * 

If An-ta ; res is on the meridian, and 66° south 
of the zenith, on July 4th, what is the ship's 
time and latitude? Ans. 9h. 31m. 10s. p.m., 
and 40° north latitude. If Al-deb'a-ran is on 
the meridian, 76|- north, on Jan. 1st, what is 
the ship's time and latitude? Ans. 9h. 48m., 
and 60° south latitude. 

The Latitude of the Ship and the name of the 
Star given, to find its Meridian Altitude rmy day 
in the year, also the time of day. 

Rule 47. Count on the Meridian the given 
degrees of latitude of the place, and call it 
Zenith. Find on the Planisphere the given star, 
and bring the Meridian to its centre. Count 
the degrees between the Star and Zenith for 
zenith distance. The zenith distaiice taken from 
90° will give the Meridian Altitude. At any 
day outside read the minute of meridian passage 
of the Star. 

A ship at sea, 60° north latitude, sees Arctu- 
rus on the meridian, wants to know its altitude 
and ship's time on June 9th? Ans. Altitude 
50°; ship's time, 8h. 58m., evening. A ship at 
sea, 50j° south, sees Fo'mal-haut on the meridian, 



12 



PROBLEMS FOR THE MOVABLE PLANISPHERES. 



wants to know its altitude and ship's time Oct. 
3rd. Ans. 70° above the north horizon ; ship's 
time, lOh. lm., evening. 

To find the Ecliptic North Pole. 

Rule 48. Bring 6 o'clock, morning, to the 
arrow at March 22nd, outside. From the North 
Pole on the Meridian count 23° 27' 20", there 
stick a pin, and call it the North Pole of the 
Ecliptic. 

To make a Graduated Meridian Line. 

Rule 49. Slip a clean piece of strong paper 
under the Meridian to the Pole. Along the 
graduated side make a mark. Commence 10° 
trom the North Pole, mark all the graduation 
marks, call each one a degree, make the five- 
marks a little longer, the ten-marks still a little 
longer, to within ten degrees of the South hori- 
zon, making 120°. F©ld the upper marks under, 
and again slip the paper under the Meridian, so 
that the line and graduation correspond. Con- 
tinue to 180°, through it stick a pin, and call it 
i Ecliptic North Pole; leaving a small circle 
around it, cut the paper on the line ; put on the 
figures to complete the Graduated Meridian Line. 

To find the Longitude and Latitude of the Sun 
any day at Mean Noon. 

Rule 50. Find the day of the month on the 
Ecliptic (the Sun's place among the stars). The 
number of degrees counted on the Ecliptic from 
March 20th (the Vernal Equinox, or first point 
Pisces) to the day of the. month is the Sun's 
Longitude in degrees. The Sun has no latitude. 

What is the latitude and longitude of the Sun 
March 20th? Ans ' 0. What is the latitude 
and longitude of the Sun Sept. 21st? Ans. 
Latitude 0, longitude 180°. 

The Latitude and Longitude of the Sun, Moon, 
Planet, Star, or Comet being given, to locate it on 
the Planisphere or Sky. 

Rule 51. Place the Meridian on the Ecliptic 
Pole by Rule 49. Count on the Ecliptic from 
the Vernal Equinox the number of degrees of 
Longitude, to which bring the Meridian. Count 
the degrees of Latitude on the Meridian from 
the Ecliptic North or South for the place of the 
Heavenly Body. 

To find the latitude and Longitude of a Star. 

Rule 52. Make a Graduated Meridian Line 
by Rule 49. Place it upon the Ecliptic North 
Pole, found by Rule 48. Then bring this Gradu- 
ated Meridian to- the centre of the Star. The 
Latitude can be counted from the Ecliptic to the 
Star, while the Longitude can be counted in 
degrees on the Ecliptic from the Vernal Equinox 
East to this Meridian Line, passing through the 
Star and Ecliptic Pole. 

Still an easier way to find tlte Latitude and Lon- 
gitude <of<i Star. 

Rule 53. Lay a straight piece of paper on 
the Ecliptic Pole to pass through the Star; at 
the Ecliptic make a mark; at the Star make an- 
other mark; and another at the Pole. Lay 
the straight piece on the Meridian, and count 
the degrees between the Ecliptic and Star mark 
for Latitude, from the Star to the Pole for the 
Polar Distance* For Longitude count the de- 
grees from the Vernal Equinox East on the 
Ecliptic to the straight edge. 

The Latitude of the place is equal to the Altitude 
of the Pole. 



Rule 54. Count from the Eqinoctial the 
number of degrees the Latitude of the place for 
Zenith distance, equal to the number of degrees 
counted from the Pole the North horizon. 

To find the Oblique Angle a Star will meet the 
Horizon in an Oblique Sphere-. 

Rule 55. Bring the Star to the Horizon, and 
notice the point of compass of meeting; then 
bring the Star up to the Meridian, and count 
its altitude from the South for about the Oblique 
Angle the Star will make when it meets the 
Horizon. 

To find what Stars are in the Circle of Perpetual 
Apparition at any place in North Latitude. 

Rule 5G. Count the number of degrees of 
Latitude from the Pole. "A radius equal to the 
altitude of the Pole above the horizon is called 
the Circle of Perpetual Apparition." — Beock- 
lesby. Turn it all around to see what Stars 
never set. 

Will Arc-tu'rus be in the circle of perpetual 
apparition in New York; if not, where will it 
be? Ans. No; but in 70° north, on the circle. 
Which star in the Dipper sets in latitude 40° 
north? Ans. Benetnash, in the end of the 
handle, not in the circle- Is Deneb, in the top 
of the Cross, in the circle of perpetual appari- 
tion in New York? Ans. No, by over 5°. 

To find ivhat Stars are in Hie Circle of Perpetual 
Occultation any place in North Latitude. 

Rule 57. Subtract the Latitude of the place 
from 90°, and count the number of degrees thus 
obtained from the Equinoctial for the South 
horizon ; turn it around the Stars, South of that 
line will be in the Circle of Perpetual Occulta- 
tion. 

Will Fo'mal-haut be seen by a person in 60° 
north latitude? Ans. No Will An-ta'res be 
seen ? Ans. Yes. 

To find the Altitude of a Star as seen from the 
North Pole. 

Rule 58. The Equator will be the horizon at 
the North Pole. The North Declination of a 
Star will be its Altitude. 

What is the altitude of Arc-tu'rus as seen from 
the North Pole? Ans. 20°. 

To find the Altitude of a Star as seen from the 
South Pole, but visible at 40° North Latitude. 

Rule 59. The Equator will be the horizon of 
the South Pole, and the South Declination will 
be its altitude read on the Meridian to 50° 
South. 

What is the altitude of Fo'mal-haut as seen 
from the South Pole. Ans. 30^°. 

To find the Altitude of a Star as seen from the 
South Pole, that is, within the Circle of Perpetual 
Occultation, in Latitude 40° North. 

Rule 60. Run a clean piece of paper under 
the Meridian, make a mark along it, and mark 
off 20° of the graduation, which call 40°, the 
radi of the small circle, pin it to its centre (the 
South Pole), and then count on it 1° for 2° from 
the South Pole, which taken from 90° will give 
the Altitude. 

What is the altitude of a CRUCIS, Southern 
Cross? Ans. South Pole distance, 28° ; its alti- 
tude, 62°. 

To find the Vernal Equinox and l 1 \rst Meridian. 

Rule 61. Bring 12 Noon to the arrow, March 
22nd. Where the Meridian meets the Equinoc- 



PROBLEMS FOR THE MOVABLE PLANISPHERES. 



13 



tial and Ecliptic, find March 20th, at the Vernal 
Equinox, the Meridian coinciding with the First 
Meridian. 

To find the Summer Solstice and its Colure. 

Rule 62. Bring 6 o'clock, evening, to the 
arrow, near March 22nd ; where the Meridian 
meets the Ecliptic, find June 21st, at the Sum- 
mer Solstice, and while the Meridian marks out 
the Summer Solstitial Colure. 

To find the Autumnal Equinox and its Colure. 

Rule 63. Bring 12 o'clock, midnight, to the 
arrow; where the Meridian meets the Ecliptic 
-and Equinoctial, find Sept. 22nd and the Autum- 
nal Equinox, the Meridian coinciding with the 
Equinoctial Colure. 

To find the Winter Solstice and its Colure. 

Rule 64. Bring 6 o'clock, morning, or 18h. 
siderial clock time or Right Ascension, to the 
arrow ; where the Meridian meets the Ecliptic, 
find Dec. 22nd at the "Winter Solstice, while the 
Meridian marks out the Winter Solstitial Colure. 

To find the Stars that shine Vertically over the 
Torrid Zone. 

Rule 65. Count on the Meridian 23° 27' 
from the Equinoctial North for the northern, and 
South for the southern, boundary of the Torrid 
Zone, all the Stars in that belt shining vertically 
over the Torrid Zone. 

Over what Zone does Reg/u-lus shine 1 Ans. 
The Torrid. 

To find the Stars that shine vertically over the 
North Temperate and North Frigid Zones. 

Rule 66. Count on the Meridian 23° 27' 
from the North Pole, which turn all around for 
the southern boundary of the North Erigid Zone, 
and the northern boundary of the North Tem- 
perate Zone ; the southern boundary of the North 
Temperate Zone being the North boundary of 
the Erigid Zone. 

Over what Zone does Arc-tu'rus shine. Ans. 
North Temperate. 

To find the Time Twilight luill begin and end, 
and the length of Total Darkness at either Pole. 

Rule 67. Twilight begins at the North Pole 
when the Sun crosses the Equator, Sept. 22nd. 
and continues to grow darker until he gets 18° 
below, or South Declination 18°, then total 
darkness until ho arrives to within 18° of the 
Equator, then twilight begins, growing brighter 
until he rises, when he arrives at the Equator, 
March 20th. When he rises at the North Pole, 
twilight then begins at the South Pole, and con- 
tinues until he gets 1 8° North ; then comes total 
darkness until he comes back to 18° North Dec- 
lination, when twilight will begin at the South 
Pole, and continue to grow brighter until he 
rises, when he arrives at the Equator. Count 
on the Meridian 1 8° from the Equinoctial, and 
bring it to meet the Ecliptic in four points . at 
each point of meeting, read the day of the month 
the San is at that place. 

When will twilight begin at the North Pole 1 
Ans. Jan. 28th, when total darkness ends. 
When will twilight end at the North Pole 1 Ans. 
Nov. 13th, when total darkness begins. When 
will twilight end at the South Pole? Ans. 
May 11th. When will twilight begin at the 
South Pole? Ans. Aug. 1st, when total dark- 
ness ends. 

To find the Harvest Moon. 



Rule 68. Find in the almanac the day the 
Moon fulls in Sept. By Rule 10 locate the 
Moon for noon that day.. Bring the Eastern 
horizon to the Moon's place. At the same day, 
outside, on the movable horizon note the time 
the Moon will rise. In the same way find the 
time the Moon will rise for several days. The 
Moon rising for several evenings so "near the 
retiring Sun, and shining all night, gives the 
harvester a good opportunity to gather in the 
fruits of his labor. 

To find the Hunters' Moon. — Burritt. 

Rule 69. Find in the almanac the day the 
Moon fulls in Oct. The same as Rule 68, find 
the time of the Moon's rising on several days. 
The Moon for these two fulls will be found to be 
rising for several evenings about the time the 
Sun will be setting : thus while the full Moon 
will be rising in the Eastern horizon, look on 
the Ecliptic for the day of the month the Sun 
setting in the Western horizon. 

When the difference of time in the Moon's rising 
is least, the difference of time in setting is greatest 

Rule 70. By Rule 68 find the least differ- 
ence of the time in the Moon's rising, or Har- 
vest Moon. Bring those several Moon's places 
to the Western horizon at the same day, outside. 
Note the difference of time of the Moon's setting 
to be the greatest. 

Changing- Seasons. To find when it will be 
Summer in any Latitude. 

Rule 71. By Rule 40 find on the Meridian 
the point to call Zenith. Move the Meridian 
over the Ecliptic until it comes nearest the 
Zenith. Count the least Zenith distance at the 
point of meeting, see the day the Sun will be 
nearest over head, or Summer. 

To find when it will be Winter in any Latitude. 

Rule 72. By Rule 40 find on the Meridian 
the point to call Zenith. Move the Meridian 
along the Ecliptic until it meets the point where 
it is at the greatest Zenith distance, at which 
point of meeting see the day the Sun's rays will 
strike the place most obliquely, or at its greatest 
Zenith distance, or Winter. 

To find wlien it will be Spring or Fall in any 
Latitude. 

Rule 73. Locate the Zenith by Rule 40 for 
places outside the Torrid Zone by moving the 
Meridian along the Ecliptic. Find the mean 
Zenith distance, or those points halfway between 
the greatest and least Zenith distance, which call 
the Equinoctial points. Note the days of each, the 
one toward which the Sun approaches call Spring, 
the one from which the Sun recedes call Fall. 

To find Astronomical and Almanac Spring. 

Rule 74. Find on the Ecliptic, March 20th, 
the Sun crossing the Line, when Astronomical 
Spring begins ; for the beginning of Almanac 
Spring, look for the first day of March. 

To find when Summer begins. 

Rule 75. Find on the Ecliptic, June 21st, the 
Sun at his greatest distance North, longest day, 
Astronomical Summer begins, but for the ac- 
cepted first day of Summer, look for June 1st. 

To find ivhen Autumn begins. 

Rule 76. Find on the Ecliptic, Sept. 22nd, 
the Sun crossing the Equinoctial, going South, 
when the Astronomical Autumn begins ; but we 
begin with the month, Sept. 1st. 



14 



PROBLEMS FOR THE MOVABLE PLANISPHERES. 



To find ivhen Winter begins. 

Rule 77. Find on the Ecliptic, Dec. 21st, the 
Sun at kis greatest Southern Declination, the 
shortest day, Astronomical Winter begins ; but 
the Almanac Winter begins Dec. 1st. 

To show the Sun rises and sets isjalse when we 
see the truth. 

Rule 78. Find the Sun's place where the day 

of the month on the Ecliptic, which the celestial 

globe makes to rise and set, but on the Plani- 

j sphere it is at rest while the horizon only moves, 

which is the truth. 

The Stars rise and set is false, taking the Mov- 
able Planisphere to be the truth. 

Rule 79. Find any Star (which does net 
move) on the Planisphere. The way to get it 
to rise or set is to move the horizon to it, East 
for rising, West for setting. By the celestial 
globe, the horizon is at rest, and the Stars move 
the reverse of truth. 

The Signs and Constellations of the Zodiac dis- 
agree, to find them as taught in the school of to-day. 

Rule 80. Look on page 4, find ' 1 . T 3« ' 
Pis'ces (the Fishes), so on for all the 12 Signs, 
as taught in the school of to-day ; also find them 
so on the painted Planisphere. 

To find the Signs and Constellations agreeing. 

Rule 81. Look on the black Planisphere; 
find the Sign of 55 Jw|g Can'cer (the Crab) all 
together; so with all the 12 Signs. Why not 
have them agree, as they will never come back. 
So from them agreeing on No. 2, 3, 4/& 5 Plani- 
spheres, page 3. . 

To find the day the Dog Star will rise with the 
Sun. 

Rule 82. Find a Sir'i-us, the Dog Star, in 
Ca'nis Ma'jor's nose, on the painted Planisphere. 
Then find it on the black one, and bring its cen- 
tre to near the E.S-E. horizon for rising. Near 
the E.N.E., where the Ecliptic meets the hori- 
zon, see the day the Sun will rise with the Dog 
Star. 

"If we look directly overhead at 10 o'clock on the 
10$ of November " — Burritt, p. 18. 

Rule 83. Bring 10 o'clock, evening, to Nov. 
10th. In the Zenith find An-drom'e-da , at her 
feet find her husband, on his knee ; on her right 
her mother;, and just behind her find her father, 
King of Ethiopia, — the royal family, not sepa- 
ated on three different maps, which I never could 
patch together on the sky, but altogether on one 
map, with all the other Stars and Constellations, 
each in its proper position in connection with 
the whole ; and move it to any minute at pleas- 
ure. • 

To locate "Telescopic Objects." — Burritt. 

Rule 84. Bring the hour and minutes of R. 
A., found on the circumference of the movable 
horizon, to the arrow at March 22nd, outside , 
under the Dec, marked on the Meridian, find 
the place of the ' Telescopic Object/ By Rule 
4, find its location on the sky at any time. 

R.A., 19h. 24m. 16s.; Dec. N., 27° 37',— to 
find Ihe Star. Ans. (3 Al-bi'reo, in the bottom 
of the Cross and in the Swan's head. 

To find lohen the "Acronical rising or setting" 
(Burritt) of a Star will occur. 

Rfle 85. Bring ihe Eastern horizon to the 
Star for Acronical rising; where the Western 



horizon meets the Ecliptic find the day ; at the 
same day, outside, read the hour and minute 
for Acronical setting. Bring the Star to the 
Western horizon, where the Eastern horizon 
meets the Ecliptic find the day, and at the day 
outside read the hour and minute it will take 
place. 

To find the Heliacal rising or setting of a Star or 
Planet. — Burritt. 

Rule 86. Bring the Eastern horizon to the 
day found on the Ecliptic, and look for the 
Stars that are Heliacally rising just above the 
Eastern horizon ; or bring the Western horizon 
to the day of the month on the Ecliptic, for the 
Stars just above the Western horizon are called 
Heliacal setting. By Rule 9 locate the Planets. 

To find ivhat bright Stars may be looked for, and 
where to see them at a total Eclipse of the Sun. 

Rule 87. Bring the moment of totality, found 
on the circumference of the movable horizon, to 
the day of the month, found on the circumfer- 
ence of the Planisphere. Again, find the day of 
the month on the Ecliptic where the Sun is, and 
around it see the Stars in their proper positions. 

"To convert the Right Ascension and Declination 
of a Body into its Longitude and Latitude." — Nor- 
ton's Astronomy, p. 70. 

Rule 88. Find the Right Ascension and 
Declination by Rule 15 ; also find the Latitude 
and Longitude by Rule 53. 

" Changing Aspect of the Heavens arising from 
the Rotation of the Earth." — Brock>esby, 40-45, 
and 134. 

Rule 89. Turn the movable horizon all round, 
observing on the circumference of the Planisphere 
the day at the hour and minute on the circum- 
ference of the movable horizon of the visible 
' starry sky,' instead of repeating what Rev. Prof. 
Brocklesby has so well said. Read it, and see 
how well the movable horizon will illustrate the 
whole mystery. 

" Circumpo'lar Constellations, and apparent move- 
ments of the Celestial Sphere." -Locylyktx, 342-344. 

Rule 90. Turn the North horizon all around, 
observing all the Stars and Constellations that 
never go down, or Circumpolar Stars. Turn the 
horizon around again, stopping every hour long 
enough to notice the Dipper, to see how remark- 
ably it changes. 

"Constellations visible in the United States on 
different evenings throughout the year. — Lockyer, 
143-152. 

Rule 91. Bring the given hour and minute, 
found on the circumference of the movable hori- 
zon, to the given day of the month, found on 
the circumference of the Planisphere. Inside the 
horizon find the stars visible, each one above the 
proper point of the compass. When so set, look 
at any other day ; see the hour or minute of the 
different days throughout the year, the same sky 
will be seen. 

What stars maybe seen "Jan. 20th, 10 p.m.;" 
and at what other times may the stars be seen in 
the very same place? Ans. Those seen in Fig. 
75, Lockyer. See in the Twins three nearly par- 
allel lines crossing three other nearly parallel 
lines of stars, crossing nearly perpendicularly; 
also the Three King, pointing out the Hy-a'des 
and Plc'ia-des on one side, Sir'i-us on the other 
side. Without changing the Planisphere, see at 



I I 



PROBLEMS FOR THE MOVABLE PLANISPHERES. 



15 



"Feb. 4th, 9 p.m.; Feb. 19th, 8 p.m.; Dec. 21st, 
midnight; Jan. 5th, 11 p.m." What stars will 
be visible "May 21st, at 10 p-m.?" Ans. Fig. 
76, Lockyer; see the stars so accurately located 
as may be easily traced a figure 2 in Bo-o'tcs ; 
Sickle in the Nortltern Crown, with 6 in Bo-o'tes. 
X, or hour-glass, in the Serpent's head. The 
parallelogram in Lion. See the Pointers point- 
ing to the pair of stars in the Bear's hind paw. 
It is uncommon to find the stars so accurately 
located. Sec the V or A, Draco's head. Even 
the small star « in Hercules. Without changing 
the horizon from "May 21st, 10 p.m.", also find 
"June 5th, 9 p.m.; May 28th, 9£ p.m.; May 6th, 
11 p.m.; April 20, midnight." 

The Movable Planisphere always stops at 365 
Daijs, Mean Clock Time, also at the same moment 
of hiderial Clock Time for any one oftlie 365 Days. 
[10.6.72, 2^ A.M.J 

Rule 92. Read 365 days on the circumfer- 
ence of the Planisphere. Oct the circumference 
of the movable horizon at each day read the 
Mean Clock Time, while the arrow near March 
22nd, outside, will point to the moment of Side- 
rial Clock Time for any one of those days. 

To show tJie Movable Planisphere correct, while 
the error in reading was but 4" and I". 

Rule 9*3. Isaac Bradford of U.S. Coast Sur- 
vey, and calculator of the almanacs, very cheer- 
fully found by the U.S. Nautical Almanac and 
mathematics the correct answer to the two ques- 
tions of Rule 22 to be : — 

lOh. 25m. 56s., and 9h. 11m. 59s., correct. 

Reading of Planisphere : — 

lOh. 26m., and 9h. 12m., small error. 

Some siderial clocks cost $200, while the set of 

Planispheres cost but $6. 

To prove the Movable Planisphere 365 times better 
tlian the Celestial Globe, by Lockyer. ( Am.Edition. ) 

Rule 94. By Rule 92 sec the Planisphere 
always ready for 365 days. By Rnle 91 set it 
fox any one of those days ; when set, it will show 
the stars above the horizon for the other days 
without any alteration. Lockyer tells us, p. 187, 
and paragraph 347, " "We next bring under the 
brazen meridian the actual place in the heavens 
occupied by the Sun at the time ; this place is 
g;iven for every day in the almanac." Taking 
the examples p. 1&9-194, we can easily see when 
we set the Planisphere for "Jan. 20th, 10 p.m." 
it will then be also set for "Feb. 4th, 9 p.m.; 
Feb. 19th, 8 p.m.; Dec. 21st, midnight; Jan. 5th, 
11 p.m.; and Fig. 75." We can as easily see the 
necessity of rectifying the globe for each day, 
and when so rectified, it will do for that day, and 
for no other. The globe costs 325, the Plani- 
spheres $3 each, or $6 a set. 

" Consequmces of the Diurnal Motion."-LoOKLis f 
p. 12, art. 13. 

Rule 95. For Star "A 1st" find, Rule 90, a 
circumpolar Star. For star " G 2nd" find by 
Rule 57 a Star in the circle of perpetual occulta 
tion. For the star "C 3rd" take a star that 
shines over the North Temperate Zone, Rule 66. 
Turn the horizon around to illustrate "Fig. 1," 
watching the arc the Star will describe. 

"Constellations visible in Nov.;" and all the 
other months in order. — Rev. John Davis, A.M., 
p. 280-332. 

Rule 96. Look over the 52 pages. Find some 



of best printed pictures of the Constellations I 
ever saw, with Stars very accurately located, so 
as to look very natural, making 30 different maps 
or pictures. Take those that are visible this 
month; find each one on the painted Plani- 
sphere ; look how accurately each star is located ; 
and then look them over together on the black 
Planisphere, and see what will be their position 
this evening; and go out and look them up on 
the firmament, to make a pleasant use of what 
we know immediately. 

"Constellations visible in September," with all the 
other months in order, tuith 1 6 beautiful plates splen- 
didly got up. — Rolfe & Jellet, p. 4-1 1 . 

Rule 97. Find the Constellations and Stars 
altogether on the painted Planispheres, and also 
on the black one. Find all the Stars as shown 
on the 1 6 plates, one looking like the sky, the 
other with tlte pictures. Find them for this 
month, and by Rule 4 find them out on the firma- 
ment at any minute desired. 

"Signs and Constellations do not agree." — J. D. 
Steele, p. 230-264, with Fig. 72. The first I 
have seen to follow the truth I have been pub- 
lishing for twenty years. Fig. 73-81. 

Rule 98. Find "Fig. 77," the figure 2 in 
Bootes, the X or hour-glass in the head of the 
Serpent, while the remainder is on "Fig. 78," 
with the Kite in Scorpio and the Milk Dipper 
beautifully shown in Sagittarius. When any of 
them are wanted to be seen, look them up on 
both Planispheres, then turn the hour and min- 
ute wanted to look for, then to the day of the 
month, then go out and find them on the clear 
sky. 

"The Southern Cross, so well shown on Fig. 
81 " can be seen in the small circle of Stars in 
perpetual occultation around South Pole. 

"To find the place of a Constellation or Star on 
the Globe." 

"Note.:— The student should be exercised in find- 
ing all the places of the Constellations or Stars laid 
down in the lists, according to this Rule." — Kiddle, 
p. 241. 

Rule 99. Try the globe, also the Planisphere, 
and use the better. " Find the place of a Con- 
stellation or Star" by Rule 15. 

I have no book on Astronomy, nor will I ; but 
want to help all the already useful books to be 
more used, and better understood by the student, 
and be with them very much more valuable than 
either alone, — in unity, each helping the other 
by helping ourselves, each keeping in his own 
sphere, to help roll on the great car of progress. 

The Movable Planisphere is always ready to 
show 365 days running under the mean clock 
time ; also at' the arrow by March 22nd, see the 
moment of the siderial clock time for any one of 
the 365 days, the hours and minutes of right 
ascension of mid heaven. Read the degrees of 
declination on the meridian over the heavenly 
object when found. 

Use the black Planisphere for correct answers. 

The two reasons for using Dr. Jane's Almanac 
are astronomically it the best, and lie gives me 
15,000 copies for gratuitous distribution, so send 
a 2-cent P.O. stamp, and get one about New- 
Year's by return mail, or send 10 cents for each 
10 you want for your astronomical class. The 
examples on page 7 are altered to suit the alma- 
nac each year to locate the planets. 



LIBRARY OF CONGRESS 



RECOMMENDATIONS. 




003 538 84£ 2 



Washington, June 3, 1868. 

Henry Whitall, Esq., 512 Arch St., Phila. 

Dear Sir, — During my late cruise I was for- 
tunately provided with one of your Movable 
Planispheres, and used it frequently. On all occa- 
sions I found it to afford reliable results, and these 
were obtained with very little trouble, and no 
difficulty. To my apprehension, it is an interest- 
ing and valuable appendage to the means of navi- 
gation, and I most cheerfully and sincerely com- 
mend its possession and use to those who follow 
the sea, or have occasion to consult the Heavens 
for Astronomical purposes. It is a great deal more 
convenient of use, particularly on board ship, 
than a celestial globe, and gives data quite as accu- 
rately. For my own part, I would not be at sea 
without one if I could help it. Yours, with much 
respect, L. M. Goldsborougii, R. Ad. U.S. N. 

U.S. Naval Observ.,Washington, D.C. 
This is to certify that I have examined a Mov- 
able Planisphere of the Heavens at Every Min- 
ute, by Henry Whitall, and that it can be relied 
upon to convert mean into siderial time to within 
a very small fraction of a minute. 

Wm. Harkness, Prof. Math. U.S. Navy. 

Georgetown College, D.C, May 9, 1864. 
Mr. Whitall has explained the use of his Plani- 
spheres to me, and I think they can be used to 
advantage for all persons who are desirous of 
improving themselves in those parts of Astrono- 
my that have reference to the celestial globe. 

James Curley, Prof, of Astronomy. 

No. 2-15.) • Permanent Com., Navy Dept. ) 
Washington, May 21, 1864. J 

Sir, — We have the honor to report that the 
Commission has had under consideration and 
examination Mr. H. Whitall's Movable Plani- 
sphere of the Heavens. This Movable Plani- 
sphere appears to have been prepared with con- 
siderable care, and as the constructions depend 
upon mathematical principles, it is entirely prob- 
able that, as far as the materials permit, paper, 
and the modes of construction, it will answer an 
excellent purpose, not only as a representation 
of the starry heavens, but as giving relative posi- 
tions of the stars of different magnitudes down 
to the fifth magnitude, and the usual figures of 
the Constellations. The problems to be 6olvcd 
are stated on the cover of the Planisphere. The 
uses of such a Planisphere are well known, also 
their conveniences in observing the paths of mete- 
ors, for which it has been employed by the mem- 
bers of the Connecticut Academy and their com- 
mittee. This Planisphere of Mr. Whitall is of a 
convenient form, and its neatness aud cheapness 
commend it to seicntific use for those purposes 
to which it is applicable. Very respectfully, 
your obedient servants : 

Hon. Gideon Welles, Secy of the Navy. 

C. H. Davis, R. Ad and Chief of B. of Nav. 

A. D. Bache, Sunt. U.S. Coast Survey. 

Joseph Henry, Secy. Smith. Institution. 

J. G. Barnard, Brig.-Gen. and Lt.-Col. Eng. 

J. Saxton, Asst. Supt. Weights and Meas. 



U. S. Coast Survey Office, ) 
Washington, May 10, 1864. \ 
Dear Sir, — I have examined your Plani- 
sphere of the Heavens, a»d have formed a very 
favorable opinion of it. It is calculated, in de- 
fault of the more expensive and less portable 
globe, to greatly facilitate a familiar acquaintance 
with the appearance of the starry firmament; 
and will be found useful not oiily to the student, 
but also to the observer of astronomical phenom- 
ena, as well as to the navigator, when he has 
occasion to use unfamiliar stars. The present 
construction of your instrument is an impro e- 
ment upon its previous form. Please supply a 
set for the use of this office. Yours, respec- 
fully, J. E. Hilgard, Asst. Coast Survey. 

" If I could not get another, I would not 
mine for Jiffy dollars. Geo. H. Chace. 

"Should be in every book- store for sale, 
in every family and school for use." — Telegn 

" I have used Mr. Whitall's Planisphere in f 
school for more than two years, and can U eh 
more of the starry heavens from it in one day 
than I can in a year from any other celestial 
atlas, map, or globe I have ever seen. 

C. B. Metcalf, Highland School, Worcester." 

Extract from the Christian Messenger, New York. 
" Old methods compared with it are like foot- 
men to a steam-engine, or a newsboy astride a 
rack of bones to the telegraph." 

" I have examined Mr. H. Y/hi tail's Movable 
Planisphere, and it seems to me to be a simple 
and economical substitute for a celestial globe, 
and capable of being used for most of the ordi- 
nary purposes to which globes are applied, and 
it is especially to be recommended ior the sim- 
plicity with which it presents to the eye some of 
the popular problems of Astronomy, and ior the 
readiness with which it will enable one to ascer- 
tain the names and positions of the stars. 

Ben. Pierce, L.L.D., Prof, of Astronomy." 

We fully concur in tho recommendation of 

Prof. Pierce of Harvard University, Cambridge, 

Mass. 

Daniel Leach, Supt. Pub. Schools, Prov. 

Alpheus Crosby, A.M., Principal State Nor- 
mal Schools, Salem, Mass. 

Henry Kiddle, Supt. Pub. Schools, N. Y. City. 

Rev. H. Mattison, High-School Astronomy. 

S. S. Randall, Supt. Pab. Schools, N. Y. City. 

Wm. Smeaton, Principal, Nor. 19. 

W. J. Schofield, 32 Summer Street, Boston. 

Thomas Foulkk, Prin. Friends' Seminary. 

Thomas Hunter, Prin., No. 35, 15th Ward. 

Thomas F. Harrison, Prin. No. 41, 9th Ward. 

Henry M. Parkhurst. 

D. C. Van Norman. 

"I am happy to recommend it to those who 
would bo glad to learn something of the starry 
heavens. • Jon.v D. Philbrick, 

Supt. Pub. Schools, Boston." 



